A couple takes their son on a cruise in an attempt to end his relationship with an unsuitable girl; a May-December couple rethink their romance; an ex-showgirl's glamorous past jeopardizes her new career as a registered nurse.

Crew members make a valiant effort to keep six stowaways a secret from Capt. Stubing; a church member disapproves of her minister's new romance; a nearly-blind woman refuses to admit her problem until Doc intercedes.

Crew members learn that Captain Stubing is under consideration to take over a prestigious cruise ship and go overboard to help their captain make an outstanding impression; a woman unknowingly makes a date with a friend's fiance; a disabled surgeon belittles Doc for practicing aboard a cruise ship until Doc makes a surprising diagnosis. GUEST STARS: Hans Conried, Ben Murphy, Donna Pescow, Carol Lynley, Richard Anderson, Diana Muldaur

Gopher invites his widowed mother onto the ship in the hopes of cheering her up, but is hurt by her seemingly cheerful attitude, which he interprets as an insult to his father. A group of buddies takes a cruise. One of the men meets a woman who is a regular customer at the restaurant where he works. He lies about his identity because he thinks she would be put off by the fact that he is a waiter. A comic's romance with the reporter who is writing a feature about him appears doomed after she takes offense to his act.

A man organizes a ""marriage-a-thon"" cruise, with special prizes to be given to the couple found to be the most compatible. At the same time, he tries to save his own crumbling marriage. Doc tricks Gopher into taking his place as one of the judges, but comes to regret it when the two attractive female judges constantly try to make time with Gopher. The single parents of one of the engaged couples come aboard with the hopes of breaking up their kids, who they think are too young to be tying the knot. A couple tries to finally get married after ten years together--and nine broken engagements. A groom decides to dump his fiancée, but skips the cruise and leaves his best man to break the news to the bride. The best man is Marv, the young man who befriended Julie when he was best man for another wedding on the Alaska cruise. He cannot bring himself to tell the bride the truth, particularly because he also has feelings for her.

Vicki tries to play matchmaker for Capt. Stubing and Emily, whose husband still plans on winning her back. Gopher lands in a Curacao jail after Doc sends him on a wild goose chase so that he can get cozy with the marriage-a-thon judges. Carl and Mary Ann decide that they were wrong to interfere with their kids' wedding plans; but their new romance drives a wedge between the couple. Mary considers calling it quits with Tom, who is physically unable to say the words ""I do"" because of his subconscious fears about marriage. Emily accuses Marv of treachery after her fiancé suddenly reappears in Curacao and denies that he planned to leave her.

Isaac forces his friends to lie to his aunt about the quality of her performance in a local play, but his plan soon backfires. Two young people grow tired of their parents' constant attempts to push them together. A single mother hopes to find romance aboard the ship. She uses her son as a judge of character--she doesn't trust anyone who causes the baby to cry.

Earthy Libby Crawford comes between socialite Miss Singleton and her escort Fedalio. Vicki meets Todd Andrews, who is traveling alone. Psychic researchers Julian and Kate Garfield search for a ghost.

The crew is in Australia to work on one of the cruise line's ships based there. And a wealthy man named Farnsworth (Lloyd Bridges) has decided to invite his whole family for a reunion, but in actuality he wants to see who, among them he should keep in his will.

After having spent time with his family, William Farnsworth (Lloyd Bridges) has finally decided who will be kept in his will.